In a small Western town fraught with tension and lawlessness, two drifters, Gil Carter and Art Croft, ride into town seeking respite and shelter after a long cattle drive. Their plans are abruptly interrupted when news spreads that a local rancher has been murdered and his cattle stolen. The townspeople, already on edge from previous cattle rustling incidents, quickly form a posse to capture the culprits. Despite the resistance of the town's more level-headed citizens, the mob is determined to take the law into their own hands. Gil and Art reluctantly join the posse, hoping to keep the situation from spiraling out of control.

As the posse rides out into the desolate wilderness, they come upon three men—Donald Martin, Alva Hardwicke, and Juan Martinez—who are caught with cattle bearing the murdered man’s brand. Circumstantial evidence and mounting hysteria drive the posse to assume the guilt of the trio, despite their protests of innocence and lack of concrete proof. The increasing pressure from key figures in the mob pushes for swift justice without proper trial or due process, leading to an intense moral conflict among the posse members. As the grim circumstances unfold, the lines between justice and vengeance blur, putting Gil and Art in a perilous position where their conscience may be at odds with the will of the mob.